Cycling has been a key part of the Olympics since the first modern Games in 1896.

It started with road and track events, with the first Olympic road race held over two laps of the marathon course.

Frenchman Paul Masson was the star of the show in Athens, winning three of the six events - the one-kilometre time trial, 10km track race and 1,000m sprint.

It was 100 years before mountain biking joined the party in Atlanta, and the introduction of several more weird and wonderful track events in Sydney took the number of different two-wheel disciplines to 11.

The advance of technology over the past century has seen bikes evolve into space-age speed machines.

The spokeless, carbon-fibre disc wheel was seen for the first time at the 1984 Los Angeles Games.

And Chris Boardman caused a huge stir at the 1992 Barcelona Olympics when he used a revolutionary new bike to become Britain's first cycling gold medallist for 72 years.

Atop an extremely light, aerodynamic machine and adopting the "Superman" position, Boardman rewrote the record books in the 4,000m individual pursuit.

Women did not compete in cycle events at the Olympics until 1984 and, at least in the case of Jeannie Longo-Ciprelli, that meant making up for lost time.

Longo has five Olympic campaigns to her name, although she had to wait until her third Games for a medal.

She crashed in the road race in Los Angeles and trailed in 21st in Seoul in 1988 before claiming silver in the event in Barcelona four years later.

She finally struck gold in the road race in Atlanta, and followed that up with silver in the road time trial, which was making its Olympic debut.

Four years ago, at the age of 41, Longo-Ciprelli won her fourth medal with bronze in the road time trial.

Other notable displays in Sydney included Leontien Zijlaard's gold medals in the women's road race, road time trial and 3,000m pursuit - as well as a silver in the points race.

Italy's Paola Pezzo will be going for a third straight gold in the women's mountain bike race in Athens, and Jan Ullrich should again be among the favourites after taking gold and silver in the men's road race and time trial in Sydney.

Ullrich's big rival, six-times Tour de France winner Lance Armstrong, won bronze in the time trial in 2000.

And the American admits he would love to add an Olympic gold to his overflowing trophy cabinet.